Đáp án:
Giải thích các bước giải:
2x³ - x² - 7x + 6 = 0
⇔ 2x³ - 2x² + x² - x - 6x + 6 = 0
⇔ (2x³ - 2x²) + (x² - x) - (6x - 6) = 0
⇔ 2x²(x - 1) + x(x - 1) - 6(x - 1) = 0
⇔ (x - 1)(2x² + x - 6) = 0
⇔ \(\left[ \begin{array}{l}x-1=0\\2x² + x - 6=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=1\\2x³ + 4x - 3x - 6=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=1\\2x(x + 2) - 3(x + 2)=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=1\\(x + 2)(2x - 3) = 0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=1\\x=-2\\x=\frac{3}{2}\end{array} \right.\)
